Artificial body members



n v 1948- F. V. .EBERLE ETAL 2,439,507

ARTIFIAGIAL BODY MEMBERS Filed April 27, .1946 2 Sheets-Sheet 1 VEN TOR. FRANK .EBEKLE v HARRY 5 Arron/Ex W? RM I l 1948. F. VQEBERLE ETAL 2,439,507

I I ARTIFICIAL BODY MEMBERS Filed April 27, 1946 2 Sheet-Sheet 2 IN V EN TOR. FRANK EBEzLE HAzz flmsm ATTOZb/EY Patented Apr. 13, 1948 um- TED STATE QFHC Agplication April '27 v laims- 3-1;);

Yet anthe ;Qhiet @o ;;.the invention:-, is ogprw V an a ificia hand and: s assembly-t: wh han and: wr t members awaretamed nst esi edrosi of r a iv rotatio yf ct n tflm tsoinm inwur aee thereon.- t anothe Qhiec tthe nventi n: i ri etnr id an wristtassembly .inlwvhich. th n em e ma -r a l tt thedtoaa d p a ed om,thewr sttmemher-a These and other objegts are efiected by the; invention as will be apparent; from 1 thefollowing description and claims taken in ,aceordance with.

the accompanying drawings, forrningfa part oft this application, in;whioh:

Fi 1' is anielevational view, partiallydn se c-. tion, of an. artificial ,wrist and. hand assembly embodying the' principles ofsfthe present I invention;

Fig. 2,is, abott omplanj view ofthe structure shownjn Fig.1;

F 3 isan expl ded ,ri w of h w ist an hand members of Fig, 1, half finel'evati'onand. half in section; l

'Fig, 4 is "a sectional View, taken along theline IV-IV of Fig. 3,; looking in-the 'direction indicated by the arrows Fig. 5 is a fragmentary viewyofamortion of the-structure shown in Figfirand;

Fig. 6 is a sectionalfview, taken along the line; VI-VIofFig. 1, looking in'-the direction indi cated by-the-arrows. 1

Referring now to the drawings-more-ln detail, the reference oharaeter I0 indicaitesQin-its entirety, anartificial hand and wrist assembly comprising a hand member Hand ai -wrist member- I2; shown locked inassembled-relation in Fig; 1 and shown separated in- Fig. 3!

Thethand member: I! comprisesa housing-T13", i shaped: and finished to simulatethe humanhand;

'The wristend 'ofthe hand housing l 3iin'clu'des an inwardly-directed flange14: against whose ,rae dial surface l fi is secured, by sorewsrl .1, a pressnre ring "I 8, iora piirposefto Joe hereinafter desc rf ed. The inner edge of the flange lAfllis,heveledftoriirervide' ar frustoeeonic'al seat [9 rot. a melting ifriistofa eqnic'al surface '21: 4 ga projeotionIzzfinteigral w th thejwristlhoiisin 2a; I

at lithe. other" nd oflthe eon co ta n rrigwa socket for the na'tnral'armsturr'ipjn the ease. of r arma put ti a 7 It should. be, inotedithat; the matin trust conical surfac s, l ajndIZJ "areoi such dime ere aSechjfrietEIiaI'enagernentflof'tliese. as: preventing A rotation of either jh'on nzg;

- relative tothe otherf' Thef frusto oonical' projection") 22 :is biseeted by' a slot 2T, milled or otherwise formed therein; arid; twdpairs" ofears or lugs" 28 extend outwardly" from the end of the projection 2 2githe' -lngjs of each 0- pair-being'diSposedat" opposite sides of -'the-* slot 21: and-*the twdpairs beingriositioned at 015130 site sides 'of'the-longitudinal axis of" the hand and wrist-'-assernbly-- I0; preferakily near the inner e-- riphery o'f-"tlie pressure ri-ng l 8 'when the 1 rist and hand"members-areassembled. 1 C3ircurnferentially- -aligned' with the te'rmi-al po'rtidnsi of the --s10t21 and with" the pairs'efi lii g st. 28--are-a-pair of bores-29 extending from the rear encl of'tlie wrist" housing "H -towards l the f-ror-lt 4=.0jor =hand *ehd thereof and-in parallel relation -tothe assembly longitudinal axisat least :adistanoe suilioient to assure that the b'ores :zs pen intdtho: bottom' of the -slet 21, whereby the two horas- 29;- incooperation with the sl'ot21, provi'de a 'pairrofv passagesiiQpen-jrOm end to end of the wrist housing.

A pair oi -bell cranks 30 and 3| are pivotally: mounted; ati.i32; to theipairs .oflugs 2.8: -Flhe bell crank: 30 oomprisesra "long; arm 33; extending": 5.0? through landab'eyondarone .oizthe bores :29 'and;;:the:., alignedi portion oflthe *slot' 21; and .a short .arm'. 34 extending. substantially at right angles :to; the long arm flawwithcits :aterminal t -portion t engaging .i the freeasurface: of; the:;pressure ringml 8; .Si-miex larly,r;theasecond be11icrank13 I comprisesyaalon f 3 arm 36 disposed in the other bore 29 and a short arm 31 likewise engaging the free surface of the pressure ring I9 at a point diametrically opposed to the point of engagement of the arm 34 of the first bell crank 30.

A relatively short lever 38 is pivotally connected, as at 39, to the free end of the long arm 33 of the first bell crank 30. One end of this lever 38 is pivotally connected, by pin40, between a pair of ears 4| at one end of a yokelike link 42 at whose other end a similar pair of ears 43 are connected by pin 44 to the free end of the long arm 36 of the second bell crank 3|. member 46 is pivoted at one end, at 47, to the other end of the short lever 38 and has its free end 43 projecting through an opening 49 in an extension 5| carried by the wrist housing 23;

Preferably, the free end 48 of the latch 46 is shaped as a knob to facilitate manipulation of the latch either manually or by engagement with any relatively stationary object. 7

, It will be apparent that the link and lever arrangement just described provides for movement of the latch inwardly and outwardly in directions transverse to the longitudinal axis of the hand and wrist assembly. In Fig. 1, the latch 46 is shown in its innermost position where it is held by engagement of a locking tooth 52, formed integral with the latch, against the inner surface of the wrist extension 5|. Downward movement of the knob 48 will disengage the locking tooth 52 from the extension 5|, permitting outward movement of the latch 46.

The linkage is so arranged that when the parts thereof are in the positions shown in Fig. 1, the short arms 34 and 31, respectively, of the bell cranks 3|] and 3|, press against the pressure rin l8 of the hand member II and urge the frustoconical surfaces I9 and 2| into sufliciently firm engagement to insure that the hand member ll cannot be rotated relative to the wrist member l2.

When the latch 46 is moved downward and the locking tooth 52 thereof disengaged from the inner surface of the wrist extension 5|, the latch is free to move outwardly and such movement will occur to at least a degree suflicient to relieve any stresses present in the linkage when in Wrist-locking position.

With the latch in unlocked position, no forces are transmitted through the linkage to the pressure plate l8, and the friction between the mating frusto-conical surfaces l9 and 21 will be so small as not to interfere with rotation of the hand member H relative to the wrist member I2.

Heretofore, hands of this character have been pretty much limited in respect to positions of adjustment of the hand member about the longitudinal axis of the hand and wrist assembly, due to the locking being accomplished by insertion of a pin into one of a series of holes or notches, and the number of positions of adjustment obtainable being limited to the number of holes or notches provided. With a hand and wrist assembly constructed in accordance with the present invention an infinite number of positions of adjustment may be obtained.

In operating the mechanism herein described, and assuming the latch 46 in unlocked position, the hand member I l is rotated to the desired position relative to the wrist member l2 and the latch pushed inwardly and upwardly until the locking tooth 52 engages the inner surface of the wrist extension 5|. As the latch moves inwardly it acts on the short lever 38, at 41, to swing the A latch lever counterclockwise about its central pivot 39, as viewed in Figs. 1, 3 and 5. The lower end of lever 38 will operate through pin 46 and ears 4| to move link 42 to the right, thereby moving radially inward the long arm 36 of bell crank 3 I. When inward movement of arm 36 has been limited b tight engagement of short arm 31 against pressure ring l8, further inward movement of latch 46 will pivot lever 38 about pin 43, thereby producing radial inward movement of long arm 33 of bell crank 33. When latch 46 is in locked position, the two short bell crank arms 34 and 31 will both press firmly upon the pressure ring 18, looking the hand and wrist members against rotation. Although as described above it appears that one bell crank moves before the other, ac-

tually they both move simultaneously, the force applied through the latch 46 being at all times equally divided between the two bell cranks. Furthermore, there actually is very little movement of the bell cranks, most of the movement of the latch merely applying stresses to, or removing stresses from, the bell cranks.

To insure that the bell cranks assume a nonstressed position relative to the pressure ring when the latch is unlocked, a bowed spring 54 is positioned with its terminal portions engaging in notches 56 in the inner edges of the long arms of. the bell cranks, the spring 54 at all times exerting forces on the bell cranks tending to move their long arms radially outward.

Where the hand member ll includes movable digits, it is desirable to provide an operating rod extending axially of the hand and wrist assembly and adapted to actuate the digits upon application of pressure or motion to the wrist end thereof. In order that the wrist joint of the present invention may be readily turnable, and'also axially separable, the operating rod comprises a first wrist section 51 and a second hand section 58 having a separable swivel connection at their adjacent ends. The operating rod wrist section,

\ wrist housing 23.

The crosshead BI is provided at its forward end with a cylindrical projection 63 terminating in an annular flange 64' having a keyway 65 inits periphery (Figs. 1 and 6). j .j

The adjacent end of the operating rod hand section 58 has a socket member 68 threadedly mounted on the operating rod, at 69, and secured there by the lock nut I I. The socket member 68 has a cylindrical bore E2 closely receiving the flange 64 of the crosshead 6|, the'borebeing provided at one side with a radial inwardly-directed key 13 slidably fitting the keyway 65. The key 13 is broken midway of its length, the gap 14 at the break being of sufficient width to re-' ceive the mating flange 64 of the crosshead, with the result that when the flange is assembledin the socket member bore l2 with the key and keyway engaging, and the parts are then rotated relative to each other, the flange 64 will be received in the gap 74 and locked against axial movement relative to the socket member. It will be noted that the end of the crosshead cylindrical portion 63 and its flange 64 do not engage the bottom of the socket member bore 12 but rest on the inner portion of the broken key 13, thereby permitting tilting of the operating rod hand; s c ien 9. i ahmiiesi e ster nec s ary in iqnl tthahen is, di i s mat n .crliiidric lrr ie i n Han diet-1i. l ther le i g o i on shown 1 andz hea refle ked e i st e iv lensitu iea crem n am an be separated rel upo rri a ion. c o e e a v to h e he thro gh d e s wher urq theik and erwa A B, w ll. be i a i nme fii ithahandhou ineHa d wrist ho sins 3.;caabesena t do lvwhe e ho ar ttotbelhcrankfii ve l es, t e l i theme s i e in deal which met e p o c s ,e ket ,633; nthe oper t n re chanism are alsoaligned, permitting complete separation of,.theihandjfrom'thewrist. When in use, the handl hou'singj Bislturned 180 degrees from the position of separation, asshown in Fig. 6. In this positionf thglateralprojections 18 of the short arm,3'l ofnbell crankje prevent this short arm frorn passing through the slot 'IJ off the pres sure ring 18. In separating the hand from the wrist, after turning the parts '180 degrees from the position shown, the shortarm 34 of bellcrank While the invention has been shown in but one form, it will be apparent to those skilled in the art that it is not so limited, but is susceptible of various changes, modifications and applications without departing from the spirit thereof.

What is claimed is:

1. In an artificial body structure, a wrist member, a hand member, a frusto-conical projection on one of said members, the other of said members having a mating frusto-conical opening adapted to closely receive said projection, and means carried by one of said members and movable between a first position where it urges the mating frusto-conical surfaces into mating relation with sufficient frictional engagement to prevent relative rotation of said surfaces and a sec-- ond position where it releases said surfaces from mating relation sufficiently to permit relative rotation thereof.

2. Structure as specified in claim 1, including a latch which when in latched position retains the last-mentioned means in its first position and when in un-latched position permits movement of said last-mentioned means to its second position.

3. In an artificial body member, a wrist member, a frusto-conical projection on said wrist member, a hand member having a frusto-conical opening in the base thereof adapted to closely receive the frusto-conical projection of the wrist member with the frusto-conical surfaces mating, and means carried by the wrist member and movable between a first position where it retains said surfaces in mating relation and a second position where it releases said surfaces from mating relation.

4. Structure as specified in claim 3, including a latch which when in latched position retains the last-mentioned means in its first position and when in unlatched position permits movement of said last-mentioned means to its second position.

5. In an artificial body structure, a wrist member, a hand member, means releasably securing said hand member to said =wrist member and adapted to lock them in any desired position orv rotation of the former relative to the latter, said securing means comprising structure providing matineisur aces. on saidinemb rsa, bel crank p litany-mount .1 1 1 or said; mbers, and m ans feranpl ing af rce one rm of said bel n rank tocauseth the arm thereofto exert pressurqiq itheotherpfsaidmembers to force saidematmelsurfaces n l lckingfrict sag men 6-; Stru ture assn cified in, cla m; ncludin means ;:for releasably locking the last-mentioned me ns ihiq cer pplying posi ion.

7 Inan; artificial body structuraa wrist member;, a ;hand-;mer nb,er, means releasably securing said hand member-to said wrist member and ad aptedatolock themin any, desired position of rotation of the. former relativeto the, latter, said secu in means comprisin structure p ov d n mating surfaces one oneach of said members, aplurality f, bell cranks pivotally mounted on one osaidmemberameans for. applying a force, toonearm on one ,ofssaid bell cranks. tocause the.Qther,, arm thereof to exert pressureon the,

other of saidmembers ,to force, said mating ,surfaces into locking frictional engagement, and e eri i t ibutine any fo pp t s d means di trib es uniiorm v of hell cranks any force applied to said one bell crank.

9. Structure as specified in claim 7, including means for releasably locking in force-applying position the means for applying a force to said one bell crank.

10. Structure as specified in claim '7, including resilient means exerting pressure on the firstmentioned arms of said bell cranks ln a direction opposed to any force applied by said forceapplying means.

11. Structure as specified in claim 5, including resilient means exerting pressure on the firstmentioned arm of said bell crank in a direction opposed to the force exerted thereon by said force-applying means.

12. In an artificial body structure, a wrist member, a hand member, a frusto-conical projection on one of said members, the other of said members having a mating frusto-conical-walled opening adapted to closely receive said projection, a plurality of bell cranks pivotally mounted on one of said members, and means for applying a force to one arm of each of said bell cranks to cause the other arm of each bell crank to exert pressure on the other of said members to force said mating surfaces into locking frictional engagement.

13. In an artificial body structure, a wrist member, a hand member, a frusto-conical projection on one of said members, the other of said members having a mating frusto-conical-walled opening adapted to closely receive said projection, a

plurality of bell cranks pivotally mounted on one of said members, means for applying a force to one arm of one of said bell cranks to cause the other arm thereof to exert pressure on the other of said members to force said mating frustoconical surfaces into locking frictional engagement, and means for distributing any force applied to said one bell crank by said force-applying means to the plurality of bell cranks for corresponding action of the latter in parallel on said other member.

14. In an artificial body structure, a wrist member, a hand member, means releasably securing said hand member to said wrist member and adapted to lock them in anydesired position of rotation of the former relative to the latter, said securing means comprising structure providing mating surfaces one on each of said members, a pair of bell cranks pivotally mounted on one of said members in opposed relation at opposite sides of the longitudinal axis of said member, a lever pivoted intermediate its terminal portions to the terminal portion of one arm of one of said bell cranks, a link pivotally joined at one end to a terminal portion of said lever and at the other end to the terminal portion of an arm of the other of said pair of bell cranks, a latch pivotally connected at one end to the other terminal portion of said lever, movement of said latch into one position operating through said lever and link to move said arms of said pair of hell cranks inopposite directions and to cause the other arm of each of said bell cranks to exert pressure on the other of said members to force said mating surfaces into locking frictional engagement.

15. Structure as specified in claim 14, including means for locking said latch in said one position.

16. In an artificial body structure, a wrist member, a hand member, means providing a pair of mating surfaces one on each of said members, a first operating rod mounted in said wrist member for sliding movement axially thereof, a second operating rod mounted in said hand member and adapted to be reciprocated by said flrst operating rod, means separablyconnecting said rods, a pair of bell .cranks pivotally mounted on said wrist member in opposed relation at opposite sides of the longitudinal axis of said operating rods, means for applying a force to one arm of one of said bell cranks to cause the other arm thereof to exert pressure on the hand member to force said mating surfaces into locking frictional engagement, and a yoke-like link having clearance with respect to said operating rods and connecting said bell cranks for distributing equally between the latter any force applied to said one bell crank by said force-applying means.

FRANK v. EBERLE. HARRY HANSEN. REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,305,169 Rohrmann May 27, 1919 1,385,669 Dilworth July 26, 1921 1,608,689 Apel Nov. 30, 1926 

